The present invention relates to the measurement of liquid flow in a living organism, and, more particularly, to such measurements performed using magnetic field measurements.
The flow and circulation of liquids in the body of a living organism are an important aspect of the health of the organism. The principal liquid flowing in the body is blood, which carries nutrients and oxygen to cells and returns waste from the cells. Irregularities in the flow of blood through the heart and blood vessels indicate the presence of constrictions or malfunctions. The irregularities in blood flow in turn often lead to other problems.
Health care workers have long monitored the flow of blood in the body, and there are a variety of techniques that can be used for this purpose. A stethoscopic examination can determine some aspects of blood flow, but this approach is quite limited. Blood flow can be monitored by injecting X-ray absorbing dyes or radioactive tracers, followed by measurements of the progress of the dyes or tracers with X-rays or radioactivity counters, respectively. These approaches, while operable, have the disadvantage of low spatial resolution, possible destruction of cells, and, in some cases, the need to inject relatively large amounts of tracer material due to the relatively low sensitivity of the techniques.
There is therefore a need for an approach that permits monitoring the flow of liquids in the body which is of high sensitivity and which produces essentially no adverse side effects. The present invention fulfills this need, and further provides related advantages.